Electrostatic charge can be built up and held on an insulator by many methods. A common method is by triboelectric generation of the charge by moving two different materials in contact with each other. As shown in FIG. 1, opposite charges (Positive + and Negative − charges) can build up on each material depending upon their ability to donate or capture electrons that are freed up due to the frictional forces generated during the movement of one material against the other. The charge that builds up on either material is called a static charge (not moving) or electro static charge. It remains on the material for some period of time depending upon the environment with which the material is in contact during the charge holding period. If the insulator holding the charge comes into contact with a conducting material the stored electro static charge can induce a charge in the conductor that can be discharged by the conductor and eventually conducted to ground.
The process of discharging the stored electrical charge is called electrostatic discharge (ESD). When an insulator carries or contains a metal conductor, the stored electrical charge on the insulator induces an equal and opposite charge on the conductor. The induced charges and/or directly deposited charges in the conductor can be conducted through the conductor into another body or to ground. If the charged insulator, containing the conductor, is inserted into or passed close to an electronic device these induced charges in the conductor can transfer into or onto the electronic device and cause disruption of the functions of the electronic device or nearby electronic devices.
The electrostatic discharge into an electronic device can occur in a variety of ways, for example, when a compact disk (CD) is inserted into a computer, a key is inserted into an electronic lock, or a plastic card containing a conducting component into a Point-of-Sale (POS) terminal. The amount of disruptions (i.e., functional disruptions) caused by the ESD within the electronic device depends on how the electrical energy from such ESD is handled by the electronic device. In many cases, the manufacturer of the electronic device takes potential ESD into consideration and designs the electronic device so that ESD will not actually or potentially disrupt the operation of the electronic device. However, there are electronic devices that require a direct insertion of an insulator carrying a conductive component directly into the device (such as a CD) as part of the functionality of the device. In such cases, the ESD can find its way into the sensitive components of the electronic device. Manufacturers use special circuit design and grounding techniques to channel the ESD energy away from sensitive components of the electronic device. However, certain electronic devices in the marketplace are not adequately designed to effectively deal with the ESD and have low tolerance to ESD. If the ESD energy is not channeled properly, then it can disrupt the operation of the electronic device.
Therefore, the present invention proceeds upon the desirability of eliminating or reducing the amount of ESD energy that an insulator carrying a conductive component can discharge into an electronic device, thereby minimizing or preventing any operational or functional disruption of the electronic device.